Uniquely identifiable inking instruments

ABSTRACT

A method of interacting with a computing device via one or more inking instruments to generate digital ink may include the steps of emitting light from a light emitting device to an inking instrument, receiving first user inputs from the inking instrument, and identifying the inking instrument based on sensed light reflected from the inking instrument. Another method may include the steps of simultaneously detecting first user inputs from a first inking instrument and second user inputs from a second inking instrument by receiving first light emitted from the first inking instrument and second light emitted from a second inking instrument that each have one or more identifying characteristics, identifying the inking instrument based on their identifying characteristics, and generating corresponding digital ink. These methods may be implemented via computer-executable instructions and may be used with a horizontally-placed display, tablet-based laptop computers, and passive or active digital inking instruments.

BACKGROUND

A variety of data entry techniques have been developed to enhanceusability and to make computers more versatile. A typical computingenvironment, especially a computing environment incorporating graphicaluser interfaces for user interaction, may be optimized for acceptinginput from one or more discrete input devices. As an example, anindividual may enter characters (i.e., text, numerals, and symbols) witha keyboard and control the position of a pointer image on a display witha pointing device, such as a mouse or trackball. A computing environmentincorporating graphical user interfaces may also accept input though oneor more natural input methods, including speech input methods andhandwriting input methods. With handwriting input methods, a pen-likestylus may be utilized to serve the general purpose of a pointing deviceand to create electronic ink.

Conventional stylus-based input devices are passive or active. Aconventional passive stylus provides a tip that applies pressure to thesurface of a touch screen apparatus. A conventional active stylusincludes electronics that interact with its computing environment todetermine the location of the stylus on the writing surface, which relyupon acoustic, magnetic or induction technology to determine thelocation information.

Conventional computing systems that interact with stylus-based inputdevices are designed to accept input from a single stylus-based inputdevice at a given time. These conventional systems do not uniquelyidentify individual stylus-based passive input devices. Further, theseconventional systems do not react differently to inputs from differentpassive stylus-based input devices, such as providing different types ofdigital ink, depending upon the input device being used.

SUMMARY

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

A method of interacting with a computing device via one or more inkinginstruments to generate digital ink is generally provided. The methodmay include the steps of emitting light from a light emitting device toan inking instrument, receiving first user inputs from the inkinginstrument, and identifying the inking instrument based on sensed lightreflected from the inking instrument.

Another method may include the steps of simultaneously detecting firstuser inputs from a first inking instrument and second user inputs from asecond inking instrument by receiving first light emitted from a firstinking instrument and second light emitted from a second inkinginstrument that each have an identifying characteristic, identifying theinking instrument based on their identifying characteristics, andgenerating digital ink that corresponds to the respective inkinginstrument.

These methods may be implemented via computer-executable instructions,and may be used with a horizontally-placed display. For example, thedisplay may be installed as a tabletop, with users sitting around theperiphery. These methods may also be used with other computing devicesthat can interact with digital inking instruments, such as tablet-basedlaptop computers or whiteboards, and may be used with passive or activedigital inking instruments. These and other features will be describedin greater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a computing system environment.

FIG. 2 illustrates an interactive table environment and interface.

FIG. 3 illustrates an example of an interactive display.

FIG. 4 illustrates a top view of the display from FIG. 3.

FIG. 5 illustrates an example passive digital inking instrument.

FIGS. 6A and 6B illustrate an example method of interacting with acomputing device, such as the interactive table environment andinterface of FIG. 2, via one or more inking instruments, such as thepassive digital inking instrument of FIG. 5.

FIG. 7 illustrates an example active digital inking instrument.

FIGS. 8A and 8B illustrate an example method of interacting with acomputing device, such as the interactive table environment andinterface of FIG. 2, via one or more active digital inking instruments,such as the active digital inking instrument of FIG. 7.

FIGS. 9A and 9B illustrate another example method of interacting with acomputing device, such as the interactive table environment andinterface of FIG. 2, via one or more active digital inking instruments,such as the active digital inking instrument of FIG. 7.

FIG. 10 illustrates another example active digital inking instrument.

FIG. 11 is a close view of a tip portion of the active digital inkinginstrument of FIG. 10.

FIGS. 12A and 12B illustrate another example method of interacting witha computing device, such as the interactive table environment andinterface of FIG. 2, via one or more active digital inking instruments,such as the active digital inking instrument of FIG. 10.

DETAILED DESCRIPTION

FIG. 1 illustrates an example of a suitable computing system environment100 on which the features herein may be implemented. The computingsystem environment 100 is only one example of a suitable computingenvironment and is not intended to suggest any limitation as to thescope of use or functionality of the features described herein. Neithershould the computing environment 100 be interpreted as having anydependency or requirement relating to any one or combination ofcomponents illustrated in the exemplary operating environment 100.

The features herein are described in the general context ofcomputer-executable instructions, such as program modules, beingexecuted by a computer. Generally, program modules include routines,programs, objects, components, data structures, etc. that performparticular tasks or implement particular abstract data types. Moreover,those skilled in the art will appreciate that the features may bepracticed with other computer system configurations, including hand-helddevices, multiprocessor systems, microprocessor-based or programmableconsumer electronics, minicomputers, mainframe computers, and the like.The features may also be practiced in distributed computing environmentswhere tasks are performed by remote processing devices that are linkedthrough a communications network. In a distributed computingenvironment, program modules may be located in both local and remotecomputer storage media including memory storage devices.

With reference to FIG. 1, the exemplary system 100 for implementingfeatures described herein includes a general purpose-computing device inthe form of a computer 110 including a processing unit 120, a systemmemory 130, and a system bus 121 that couples various system componentsincluding the system memory to the processing unit 120.

Computer 110 may include a variety of computer readable media. By way ofexample, and not limitation, computer readable media may comprisecomputer storage media and communication media. The system memory 130may include computer storage media in the form of volatile and/ornonvolatile memory such as read only memory (ROM) 131 and random accessmemory (RAM) 132. A basic input/output system 133 (BIOS), containing thebasic routines that help to transfer information between elements withincomputer 110, such as during start-up, may be stored in ROM 131. RAM 132may contain data and/or program modules that are immediately accessibleto and/or presently being operated on by processing unit 120. By way ofexample, and not limitation, FIG. 1 illustrates operating system 134,application programs 135, other program modules 136, and program data137.

The computer 110 may also include other removable/nonremovable,volatile/nonvolatile computer storage media. By way of example only,FIG. 1 illustrates a hard disk drive 141 that reads from or writes tononremovable, nonvolatile magnetic media, a magnetic disk drive 151 thatreads from or writes to a removable, nonvolatile magnetic disk 152, andan optical disk drive 155 that reads from or writes to a removable,nonvolatile optical disk 156 such as a CD ROM or other optical media.Other removable/nonremovable, volatile/nonvolatile computer storagemedia that can be used in the exemplary operating environment include,but are not limited to, magnetic tape cassettes, flash memory cards,digital versatile disks, digital video tape, solid state RAM, solidstate ROM, and the like. The hard disk drive 141 may be connected to thesystem bus 121 through a non-removable memory interface such asinterface 140, and magnetic disk drive 151 and optical disk drive 155may be connected to the system bus 121 by a removable memory interface,such as interface 150.

The drives and their associated computer storage media discussed aboveand illustrated in FIG. 1 may provide storage of computer readableinstructions, data structures, program modules and other data for thecomputer 110. In FIG. 1, for example, hard disk drive 141 is illustratedas storing operating system 144, application programs 145, other programmodules 146, and program data 147. Note that these components can eitherbe the same as or different from operating system 134, applicationprograms 135, other program modules 136, and program data 137. Operatingsystem 144, application programs 145, other program modules 146, andprogram data 147 are given different numbers here to illustrate that, ata minimum, they are different copies. A user may enter commands andinformation into the computer 110 through input devices such as akeyboard 162 and pointing device 161, commonly referred to as a mouse,trackball or touch pad. Other input devices (not shown) may include amicrophone, joystick, game pad, satellite dish, scanner, or the like.These and other input devices are often connected to the processing unit120 through a user input interface 160 that is coupled to the systembus, but may be connected by other interface and bus structures, such asa parallel port, game port or a universal serial bus (USB). A monitor191 or other type of display device may also be connected to the systembus 121 via an interface, such as a video interface 190. The videointerface 190 may be bidirectional, and may receive video input fromsensors associated with the monitor 191. For example, the monitor 191may be touch and/or proximity sensitive, such that contacts to a monitorsurface may be used as input data. The input sensors for affecting thiscould be a capacitive touch sensitive device, an array of resistivecontact sensors, an optical sensor or camera, or any other desiredsensor to make the monitor 191 touch and/or proximity sensitive. In analternative arrangement, or in addition, a touch and/or proximitysensitive input system may be separate from monitor 191, and may includea planar surface such as a table top 192 and any applicable sensingsystems to make the planar surface touch sensitive, such as camera 193.In addition to the monitor, computers may also include other peripheraloutput devices such as speakers 197 and printer 196, which may beconnected through an output peripheral interface 195.

The computer 110 may operate in a networked environment using logicalconnections to one or more remote computers, such as a remote computer180. The remote computer 180 may be a personal computer, and typicallyincludes many or all of the elements described above relative to thecomputer 110, although only a memory storage device 181 has beenillustrated in FIG. 1. The logical connections depicted in FIG. 1include a local area network (LAN) 171 and a wide area network (WAN)173, but may also include other networks.

When used in a LAN networking environment, the computer 110 may beconnected to the LAN 171 through a network interface or adapter 170.When used in a WAN networking environment, the computer 110 may includea modem 172 or other means for establishing communications over the WAN173, such as the Internet. The modem 172, which may be internal orexternal, may be connected to the system bus 121 via the user inputinterface 160, or other appropriate mechanism. In a networkedenvironment, program modules depicted relative to the computer 110, orportions thereof, may be stored in the remote memory storage device. Byway of example, and not limitation, FIG. 1 illustrates remoteapplication programs 185 as residing on memory device 181. It will beappreciated that the network connections shown are exemplary and othermeans of establishing a communications link between the computers may beused. Many of the features described herein may be implemented usingcomputer-executable instructions stored on one or more computer-readablemedia, such as the media described above, for execution on the one ormore units that make up processing unit 120.

The computing device shown in FIG. 1 may be incorporated into a systemhaving table display device 200, as shown in FIG. 2. The display device200 may include a display surface 201, which may be a planar surfacesuch as a table top. As described hereinafter, the display surface 201may also help to serve as a user interface.

The display device 200 may display a computer-generated image on itsdisplay surface 201, which allows the device 200 to be used as a displaymonitor for computing processes, displaying television or other visualimages, video games, and the like. The display may be projection-based,and may use a digital light processing (DLP) technique, or it may bebased on other display technologies, such as liquid crystal display(LCD) technology. A projector 202 may be used to project light onto theunderside of the display surface 201. It may do so directly, or may doso using one or more mirrors. As shown in FIG. 2, the projector 202projects light for a desired image onto a first reflective surface 203a, which may in turn reflect light onto a second reflective surface 203b, which may ultimately reflect that light onto the underside of thedisplay surface 201, causing the surface 201 to emit light correspondingto the desired display.

In addition to being used as an output display for displaying images,the device 200 may also be used as an input-receiving device. Asillustrated in FIG. 2, the device 200 may include one or more lightemitting devices 204, such as IR light emitting diodes (LEDs), mountedin the device's interior. The light from devices 204 may be projectedupwards through the display surface 201, and may reflect off of variousobjects that are above the display surface 201. For example, one or moreobjects 205 may be placed in physical contact with the display surface201. One or more other objects 206 may be placed near the displaysurface 201, but not in physical contact (e.g., closely hovering). Thelight emitted from the emitting device(s) 204 may reflect off of theseobjects, and may be detected by one or more cameras 207, which mayinclude one or more infrared (IR) cameras if IR light is used. Thesignals from the one or more cameras 207 may then be forwarded to acomputing device (e.g., the device shown in FIG. 1) for processing,which, based on various configurations for various applications, mayidentify the object and its orientation (e.g. touching or hovering,tilted, partially touching, etc.) based on its shape and the amount/typeof light reflected.

To assist in identifying the objects 205, 206, the objects may include areflective pattern, such as a bar code, on their lower surface. Toassist in differentiating objects in contact 205 from hovering objects206, the display surface 201 may include a translucent layer thatdiffuses emitted light. Based on the amount of light reflected back tothe camera 207 through this layer, the associated processing system maydetermine whether an object is touching the surface 201, and if theobject is not touching, a distance between the object and the surface201. Accordingly, various physical objects (e.g., fingers, elbows,hands, stylus pens, blocks, etc.) may be used as physical controlmembers, providing input to the device 200 (or to an associatedcomputing device).

The device 200 shown in FIG. 2 is illustrated as using light projectionand/or sensing techniques for the display of data and the reception ofinput, but other techniques may be used as well. For example,stylus-sensitive displays are currently available for use withTablet-based laptop computers, and such displays may be used as device200. Additionally, stylus- and touch-sensitive displays are availablewith many personal data assistants (PDAs), and those types of displaysmay also be used as device 200.

The device 200 is also shown in a substantially horizontal orientation,with the display surface 201 acting as a tabletop. Other orientationsmay also be used. For example, the device 200 may be oriented to projecta display onto any desired surface, such as a vertical wall. ReflectiveIR light may also be received from any such oriented surface.

FIG. 3 illustrates an illustrative configuration of an implementation ofthe system shown in FIG. 2, in which device 301 is used as a tabletopdisplay device. FIG. 4 illustrates an overhead view of such a table,around which a number of users 401 may be seated or standing. Each user401 may wish to interact with the display on the surface of table 301,for example to draw, place and/or touch an object, or to play a partyvideo game.

FIG. 5 illustrates a passive digital inking instrument 500 that can beused as an input device along with the system shown in FIG. 2. Althoughinking instrument 500 is electronically passive and generally does notelectronically interact with computer system 200, it can be uniquelyidentified by the computer system based upon its vision properties.Inking instrument 500 reacts to the light emitted from the one or moreof the light emitting devices 204 of computing system 200 and, thereby,provides light that has one or more identifying characteristics to theone or more cameras 207. For example, inking instrument 500 may reflectthe emitted light (or certain wavelengths of the emitted light) at aparticular reflectivity, or within a particular range of reflectivities,such that the amount of the reflected light is an identifyingcharacteristic for the inking instrument. In one configuration, inkinginstrument 500 has a reflectivity within a particular range for aparticular wavelength of light emitted from the one or more lightemitting devices 204. The computing system can, thereby, identify inkinginstrument 500 based on the amount of light emitted from emitting device204 that is reflected by the inking instrument to camera 207.

As an example, light emitting device 204 can emit infrared light at 850nm through the display surface 201 to inking instrument 500. It may bedesirable for light emitting device 204 to emit light at a wavelengththat is not visible by humans, but that is recognizable by camera 207,so that it does not affect the viewable image displayed on displaysurface 201. For example, it may be desirable for the light emittingdevice to emit light within the infrared light range. A tip portion 504of the inking instrument can reflect a portion of the emitted light(e.g., 50%-60%), which can be sensed by camera 207. Computing system canidentify inking instrument by the amount of light it reflects. In oneconfiguration, computing system 200 can uniquely identify inkinginstrument based on a calculated reflectivity for the instrument (e.g.,if the ratio of the amount of reflected light to the amount of emittedlight is 55% plus or minus 5%). In another configuration, it may do sobased on the amount of sensed reflected light being greater than or lessthan a threshold value (e.g., it is less than 60% of the amount ofemitted light.)

As shown in FIG. 5, instrument 500 includes a handle 502 and a tipportion 504 having bristles 506 extending therefrom. The bristles areconfigured to have a desired range of reflectivity properties for one ormore wavelengths of light, which permits the instrument to be uniquelyidentified by the computing system and can permit two or more of theinstruments having different properties to be simultaneously anduniquely identified by the system. For example, two users of computingsystem 200 using different inking instruments 500 that have differentreflectivities could simultaneously use the computing systems withouttheir inputs being confused by the system.

The reflectivity of inking instrument 500 for particular wavelengths canbe configured as desired based on the properties of bristles 506. A widevariety of materials may be used to provide the desired reflectivity attip portion 504, which may or may not include bristles. For example,various types of foam materials may be placed at tip portion 504 toprovide an interface with the table top/writing surface 201 and toprovide a desired reflectivity. Further, various types of bristlematerials may be used, such as synthetic materials (e.g., nylon andpolyester) and natural materials (e.g., pony, ox, hog or camel hair).The materials may be treated with colorants or other chemicals toincrease or decrease their reflectivity as desired for one or morewavelengths of light. The number of uniquely identifiable inkinginstruments 500 that could be used with a particular computing systemmay depend upon the sensitivity of the device receiving reflected lightfrom the inking instrument, the power of the illumination source(s) fora particular computing system, the number of different illuminationsource wavelengths, and vision characteristics of the inking instruments(e.g., their reflectivity.)

FIGS. 6A and 6B illustrate example configurations and methods ofinteracting with computing device 200 via a plurality of passive digitalinking instruments similar to inking instrument 500, but which havediffering vision characteristics. The example inking instruments includeBrush A 610, Brush B 612 and Brush C 614 having different visioncharacteristics for one or more wavelengths of light emitted fromemitting device 204. Each of these instruments includes a handle 616 forthe user to grip and a tip portion 618, 620 or 622. The tip portionshave differing reflectivities for a given wavelength of light, whichpermits them to be uniquely identified by computing system 200.

As an example configuration, which may be according to FIG. 6A, assumeemitting device 204 emits infrared light having a wavelength of 850 nmtoward tabletop 201. Assume further that Brush A has a reflectivitybetween 50%-60% for that wavelength of light, Brush B has a reflectivitybetween 70%-80%, and Brush C has reflectivity between 90%-100%. For suchan example configuration, Brush A may include highly reflectivesynthetic bristles, such as nylon or polyester, or highly reflectivenatural bristles, such as hog hair. Brush B may include moderatelyreflective natural bristles, such as pony, ox or camel hair bristles.Further, Brush C may include foam or another material having relativelylow reflectivity. All three of these brushes may simultaneously beplaced on table top 201 and, thereby, reflect the infrared light fromemitting device 204 to camera 207.

As shown in FIG. 6B, the system senses the inking instruments 610, 612and 614 differently depending on the amount of infrared light at 850 nmthat is reflected by each instrument and sensed by camera 207. Brush Ahas the highest reflectivity and, thus, camera 207 senses more light forimage 624 reflected by Brush A than the other inking instruments. BrushB has the next highest reflectivity and, thus, camera 207 senses lesslight for image 626 as reflected by Brush B. Similarly, the camerasenses the least amount of light for image 628 reflected by Brush C.Based on the amount of light sensed for each of these images, computingsystem 200 is able to identify each of these images as corresponding todifferent inking instruments.

Unique identification of different inking instruments provides variousadvantages. For example, it permits computing system 200 to uniquelymark or identify the digital ink created via inputs from each inkinginstrument as corresponding to the particular instrument. In the exampleabove, Brushes A, B and C may each generate different colors of digitalink on computing system 200 according to user preferences and/or systemsettings for the computing system. The brushes may be used by a singleuser who desires to use different inking instruments depending on thedesired characteristics for the ink. For instance, the user may use afirst instrument (e.g., Brush A) to create digital ink having a firstcharacteristic, such as one or more of a first desired color, texture,style, weight for the digital ink. The user may use a second instrument(e.g., Brush B) to create ink having a second characteristic and a thirdinstrument (e.g., Brush C) to create ink having a third characteristic.The user can interact with computing system 200 to identify desired inkcharacteristics for different inking instruments.

The brushes may also be used simultaneously by a single user or bymultiple users. When used by multiple users, marking the digital ink(e.g., by color, weight or style) according to the particular inkinginstrument permits the users to easily identify their personal inputs.This may be particularly beneficial in a group setting, such as duringgame play with computing system 200. Further, uniquely identifyinginputs according to the inking instrument may be beneficial foridentifying which inputs were made by whom, such as who was the firstperson to select a particular object on the table top during game play.

FIG. 7 illustrates an example active digital inking instrument in theform of a light pen 710 that can be uniquely identified by computingsystem 201 via one or more characteristics of the light being emittedfrom the inking instrument. As shown, pen 710 can include a light source712, optional inputs (e.g., buttons) 714 for changing one or morecharacteristics of the emitted light, a power supply 716, and a filtermechanism 718. The various components may be electrically coupled asnecessary using, for example, a bus (not shown). The power supply 716may be incorporated into the inking instrument or may externally beprovided via an electrical connection with the host computing system200. The pen may include a processor (not shown) or other mechanical orelectronic components that can permit the user to select and changecharacteristics of the emitted light. Alternatively, the pen may onlyprovide emitted light having one or more preset characteristics.

Light source 712 may be fixed light source that emits a particularamount of light of a certain wavelength or a range of wavelengths. Inaddition, light source 712 may have variable settings to produce lightat differing power levels, wavelengths, etc. Filter mechanism 718 may bea cut filter to permit the light pen to emit light 720 in a particulargeometric shape (e.g., a rectangle, triangle, circle, etc.) 722. Filtermechanism may also include optical filters to permit certain wavelengthsof light to be emitted from the light pen while restricting otherwavelengths. Optional inputs 714 may be used to change the settings ofthe light source for a variable light source configuration and/or toadjust characteristics of the filter mechanism (e.g., to select aparticular shape or wavelength).

FIGS. 8A and 8B illustrate an example method of interacting with acomputing device, such as computing device 200, via one or more activedigital inking instruments, such as the active digital inking instrumentof FIG. 7. Suppose, as an example, that multiple light pens 710 areconfigured to form Light Pen A 810 emitting infrared light in the shapeof an oval 816, Light Pen B 812 emitting infrared light in a rectangularshape 818, and Light Pen C 814 emitting infrared light in a triangularshape 820. As shown in FIG. 8B, camera 207 would receive the emittedlight from the pens as differently shaped inputs, which can permitcomputing system 200 to uniquely identify the inputs according to thepen providing the input.

In an alternative configuration for light pen 710, which can also berepresented by FIG. 8A, different light pens can emit modulating lightsin differing patterns. For example, Light Pen A could emit light pulsesin a distinct pattern, such as on-on-off, Light Pen B could emit lightpulses in an off-off-on pattern, and Light Pen C could emit light pulsesin an on-on-on pattern. Computing system 200 can uniquely identify thedifferent light pens by recognizing the pattern emitted by each pen. Itis understood that the distinct patterns could be generated in a varietyof different ways with a variety of mechanisms. For example, they couldbe created by modulating the light with higher and lower intensities,different wavelengths or colors, different frequencies, etc., and viacombinations of various mechanisms (e.g., on-off pulses combined withpulses at different intensities).

As further shown in FIG. 8A, light pens 810, 812 and 814 can interactwith table top 201 at various distances from the table top depending onfactors such as the strength of the light being emitted and thesensitivity of camera 207. As with the passive inking instrumentsdiscussed above, light pens 810, 812 and 814 can be uniquely identifiedby the computing system, which can sense the geometric shapes of theemitted lights. The use of geometric shapes can provide additionaladvantages, such as providing orientation information for the light penand distance information. When such a light pen is further from thetable top, the size of the emitted geometric shape sensed by camera 207is larger and less defined than when the light pen is in contact withthe table top. The size and/or clarity of the sensed shape can be usedby the computing system to evaluate the distance of the respective penfrom the table top.

FIGS. 9A and 9B illustrate another example method of interacting with acomputing device, such computing device 200, via one or more activedigital inking instruments, such as the active digital inking instrumentof FIG. 7. As shown in FIG. 9A, a first inking instrument includes LightPen A 910 emitting light 914 at a first frequency and Light Pen Bemitting light 916 at a second frequency different from Light Pen A.Suppose, as an example, that Light Pen A emits infrared light having awavelength of 800 nm and Light Pen B emits infrared light having awavelength of 850 nm. Suppose further that camera 207 includes aplurality of cameras including a first camera that senses infrared lightat 800 nm and a second camera that senses infrared light at 850 nm.Thus, as shown in FIG. 9B, the first camera could sense inputs fromLight Pen A, but not from Light Pen B. Similarly, the second cameracould sense inputs from Light Pen B, but not from Light Pen A. As such,computing system 200 could uniquely and simultaneously identify inputsfrom Light Pen A and from Light Pen B.

FIG. 10 illustrates another example active digital inking instrument1010, which generally includes the aspects and preferences of passiveinking instrument 500 of FIG. 5, along with the active featuresdescribed below. Similar to inking instrument 500, inking instrument1010 is configured as a brush having a handle 1012 and bristles 1014.However, bristles 1014 include both passive reflective bristles (e.g.,bristles 506 as discussed along with inking instrument 500) and anarrangement of fiber optic bristles (see FIG. 11). The fiber opticbristles are intermingled with the passive bristles in variousarrangements to assist with uniquely identifying the brush and/orvisibly identifying to the user the current inking characteristics forthe brush (e.g., the current ink color associated with the particularinstrument). As shown in FIG. 11, fiber optic bristles 1110 are eachconnected to a light source 1112, 1114 or 1116 that can illuminate theindividual fiber optic bristles as desired. The light sources 1112, 1114and 1116 can emit light having different characteristics, such asdifferent colors. In one configuration, the light sources emit theprimary colors (red, yellow and blue). For instance, light source 1112can emit red light, light source 1114 can emit yellow light and lightsource 116 can emit blue light. In addition, the light sources can emitvisible and/or non-visible light (e.g., infrared light).

The combination of fiber optic and non-fiber optic bristles can create awide variety of uniquely identifiable reflective patterns, which can besensed by camera 207. As illustrated in FIGS. 12A and 12B, selected onesof the fiber optic bristles can be emit light at the same wavelength asemitting device 202 and others can emit light at another wavelength tocreate an identifiable pattern for camera 207. Thus, a wide variety ofunique patterns can be created to identify different inking instruments.For example, in the example illustrated in FIG. 12A, fiber optic fibers1236 of Brush A are emitting light at the same wavelength and intensityas the reflected light from Brush A being sensed by the camera, whilefiber optic fibers 1234 are not emitting light or are doing so at adifferent wavelength than what is being sensed by camera 207. Fiberoptic fibers 1234 of Brush B are emitting light at the same wavelengthand intensity as the reflected light from Brush B being sensed by thecamera, while fiber optic fibers 1236 are not emitting light or aredoing so at a different wavelength than what is being sensed by camera207. Neither fiber optic fibers 1234 or 1236 on Brush C are emittinglight or are doing so at a different wavelength than what is beingsensed by camera 207. As such, Brushes A, B and C can be identified viathe amount of light being reflected from their bristles and/or via thepattern created by the fiber optic fibers.

Referring back to FIG. 10, inking instrument 1010 can changeconfigurations by illuminating fiber optic fibers in various patterns,colors and configurations. Inking instrument 1010 can include aprocessor 1016, a receiver 1018, a transmitter 1020, a power source 1022and/or other mechanisms that can cooperate with each other to power thelight sources and to change the configuration of illuminated fiber opticfibers as desired. Inking instrument 1010 may also include inputs 1024through which the user may select a desired configuration. The abilityto selectively illuminate various fiber optic fibers permits a singleinking instrument to represent different uniquely identifiable inkinginstruments depending upon its configuration of illuminated fiber opticfibers. For example, a user could initially use inking instrument 1010to produce digital ink having a first characteristic, such as a firstcolor. Rather than interacting with the computing system to change thedigital ink color, the user could select a different configuration ofilluminated fiber optic fibers that are associated with an inkinginstrument that produces digital ink on the system having a secondcharacteristic (e.g., a second color). Thus, the user could use a singleinstrument to represent different uniquely identifiable instruments assensed by the computing system.

In addition, the fiber optic fibers could provide the added benefit ofemitting visible light along with non-visible light (e.g., infraredlight). As such, the fiber optic fibers could emit visible light toidentify the current configuration of the inking instrument to the user,while also emitting infrared light for identifying the inking instrumentto the system. For instance, some of the fiber optic fibers could emitred light to visibly indicate to the user that the inking instrument iscurrently associated with red digital ink on the computing system.

Fiber optic bristles can provide the further benefit of sensing inputsfrom the computing system or from other sources. For example, table top201 could display a palette of colors. The user could place inkinginstrument 1010 in contact with, or proximate to, a desired color on thepalette while inking instrument 1010 is in a color-sense mode. Thedesired color on the palette could be sensed by the inking instrumentvia light received at the fiber optic fibers to identify the colorselected on the palette. The fiber optic bristles could thereafterilluminate one or more visible lights and visibly identify to the userthe ink color currently associated with the inking instrument. Thecomputing system could also sense user-selection of the color from thedisplay and associate that color with the inking instrument.Alternatively, signals received at sensor 1118 (FIG. 11) or via receiver1018 (FIG. 10) from computing system 200 could identify a selected coloror other inking characteristic to the inking instrument, which couldvisibly indicate the selected color to the user by illuminatingappropriate fiber optic fibers.

Using one or more of the features and approaches described above, one ormore user's interaction with a computing device can be improved.Although the description above provides illustrative examples andmethods, it should be understood that the various examples and sequencesmay be rearranged, divided, combined and subcombined as desired.Accordingly, although the subject matter has been described in languagespecific to structural features and/or methodological acts, it is to beunderstood that the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described above.Rather, the specific features and acts described above are disclosed asexample forms of implementing the claims.

1. A method of interacting with a computing device via one or moreinking instruments to generate digital ink, the computing device havinga light emitting device and a light sensing device, the methodcomprising the steps of: emitting light from the light emitting deviceto a tip portion of an inking instrument; and receiving user inputs fromthe inking instrument, the step of receiving user inputs comprising:receiving, at the light sensing device, reflected light reflected fromthe tip portion of the inking instrument; and identifying the inkinginstrument based on one or more characteristics of the sensed reflectedlight.
 2. The method of claim 1, further comprising: displaying adigital ink object based on the received user inputs; and visiblymarking the digital ink object as corresponding to the inkinginstrument.
 3. The method of claim 2, wherein the step of visiblymarking the digital ink object includes displaying the digital inkobject using a first color.
 4. The method of claim 1, wherein the inkinginstrument is a first inking instrument, the method further comprising:receiving user inputs from a second inking instrument, the step ofreceiving user inputs from the second inking instrument comprising:receiving, at the light sensing device, reflected light reflected from atip portion of the second inking instrument; and identifying the secondinking instrument based on one or more characteristics of the sensedreflected light from the second inking instrument, the one or morecharacteristics of the sensed reflected light from the second inkinginstrument differing from the one or more characteristics of the sensedreflected light from the first inking instrument.
 5. The method of claim4, further comprising: displaying a first digital ink object based onthe received first user inputs and a second digital ink object based onthe received second user inputs; and visibly marking the first digitalink object as corresponding to the first inking instrument and thesecond digital ink object as corresponding to the second inkinginstrument.
 6. The method of claim 5, wherein the step of visiblymarking includes displaying the first digital ink object using a firstcolor and the second digital ink using a second color different than thefirst color.
 7. The method of claim 4, wherein, for the step of emittinglight, the emitted light has a wavelength and, for the steps ofreceiving user inputs from the first and second inking instruments, thereflected light from the first and second inking instruments have thesame wavelength as the emitted light.
 8. The method of claim 7, whereinthe steps of receiving user inputs from the first and second inkinginstruments each include the step of diffusing the reflected light fromthe first and second inking instruments to reduce the transmission ofthe reflected lights to the light sensing device when the first andsecond inking instruments are not proximate a digital writing surface ofthe computing device.
 9. The method of claim 4, wherein, for the stepsof identifying the first and second inking instruments, thecharacteristics of the sensed reflected light from the first and secondinking instruments include the amount of the sensed reflected lights incomparison with the amount of the light emitted from the emittingdevice.
 10. The method of claim 1, wherein the step of receiving userinputs further includes: receiving, at the light sensing device, apattern of lights emitted from the inking instrument; and selectingcharacteristics for digital ink corresponding to inking instrument basedon the received pattern of lights.
 11. The method of claim 10, whereinthe pattern of lights includes a first light emitted from the inkinginstrument spaced apart from a second light emitted from the inkinginstrument.
 12. A method of interacting with a computing device via aplurality of inking instruments to generate digital ink, the methodcomprising the steps of: simultaneously detecting first user inputs froma first inking instrument and second user inputs from a second inkinginstrument, the step of simultaneously detecting first and second userinputs comprising: simultaneously receiving first light emitted from afirst inking instrument contacting a display surface of the computingdevice and second light emitted from a second inking instrumentcontacting the display surface, the first light having a firstidentifying characteristic, the second light having a second identifyingcharacteristic differing from the first identifying characteristic;identifying the first inking instrument based on the first identifyingcharacteristic; and identifying the second inking instrument based onthe second identifying characteristic; generating digital ink displayinga first object having a first distinguishing feature, the firstdistinguishing feature corresponding to the first inking instrument; andgenerating digital ink displaying a second object having a seconddistinguishing feature, the second distinguishing feature correspondingto the second inking instrument.
 13. The method of claim 12, wherein thefirst identifying characteristic includes a first geometric shape andthe second identifying characteristic includes a second geometric shapedifferent than the first geometric shape.
 14. The method of claim 12,wherein the first identifying characteristic includes a first lightwavelength and the second identifying characteristic includes a secondlight wavelength different than the first light wavelength.
 15. Themethod of claim 12, wherein the first identifying characteristicincludes a first pattern of lights and the second identifyingcharacteristic includes a second pattern of lights.
 16. The method ofclaim 12, wherein the step of simultaneously receiving first and secondlights includes diffusing the first and second lights emitted from thefirst and second inking instruments to reduce the reception of theemitted first and second lights when the first and second inkinginstruments are not proximate a digital writing surface.
 17. A kit forinteracting with a computing device to generate digital ink, the kitcomprising: a first inking instrument having a first reflectivity for aspecified light wavelength; a second inking instrument having a secondreflectivity for the specified light wavelength, the second reflectivitydiffering from the first reflectivity by 1% or more; and a computerreadable medium having computer readable instructions stored thereon forperforming steps comprising: identifying the first inking instrumentbased on one or more characteristics of reflected light at the specifiedlight wavelength received at a light sensing device as reflected by thefirst inking instrument from light emitted from a light source; andidentifying the second inking instrument based on one or morecharacteristics of reflected light at the specified light wavelengthreceived at the light sensing device as reflected by the second inkinginstrument from light emitted from the light source.
 18. The kit ofclaim 17, wherein the computer readable medium includes computerreadable instructions for performing further steps comprising:generating first digital ink having a first identification featurecorresponding to the first inking instrument; and generating seconddigital ink having a second identification feature corresponding to thesecond inking instrument.
 19. The kit of claim 18, wherein the firstidentification feature includes a first color and the secondidentification includes a second color different than the first color.20. The kit of claim 18, wherein the second reflectivity differs fromthe first reflectivity by 5% or more.